Definition

A port-wine stain is a mark that is usually present at birth. It is made of enlarged blood vessels. This makes it appear as a reddish-purple patch of skin.

Port-wine stains are generally harmless. They may cause emotional and social problems due to their visibility.

Causes

Port-wine stains are caused by a problem with the small blood vessels in the skin. Blood vessels can normally open and close to meet the needs of the skin. In port-wine stains, the blood vessels stay wide open. Blood fills the vessels causing the purple color and raised skin. It is not clear what causes the problems with the blood vessels.

Risk Factors

There are no known risk factors for port-wine stains.

Conditions associated with port-wine stains include:

Sturge-Weber syndrome

Klippel-Trenaunay-Weber syndrome

Symptoms

Symptoms include a mark that may be:

Reddish or purplish in color in adults

A flat, red or light purple lesion in children

Raised in adults

On the head or neck

Bleeding when scratched

Dark and thick over time

A port-wine stain near the eyes may cause other problems.

Diagnosis

A port-wine stain can typically be diagnosed based on its appearance. In some rare cases, a
skin biopsy
may be done.

Since some stains may also be associated with other medical conditions, your doctor may order other tests to look for any of these related conditions.

Prevention

Revision Information

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.